Rubber tire.



Patented Aug. 31,1915.

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KROTZ, F JANESVILLE, WISCONSIN.

RUBBER, TIRE.

Specification of Letters atent.

Patented ring. Bil, MM5

application alec. April 20, wie. Serial No. 833,093.

o @ZZ '1c/1.0m t may concern it known that il.,

citizen ot the `United Sit of hnierica,

and resident of lanewilevioclr 'county,

liscoii --ivented a certain new and useful in Rubber Tires, of

which the' iollmvingy a si'ieciication.

ihis is an impro.'ement on the construction disclosed in my priorapplication 785.13' .iied August 1G, i013.

7 invention relates to rubber vehicle at kind in which a solid andcention provided at each side an irregular audace formed tion and otherelements that the tire will be ellcient and durable in use, and willalso tirely satisfactory in other Ways, .not only from the standpoint ofthe user, but from that of the manufactura' as Well.

lo these and other useful ends my invention consists in mattershereinafter set forth and claimed.

ln the accompanying drawings-l1`igure 1 is a section oi. a rubber tireembodying the principles of my invention. Fig. 2 is a side eleyatitm ota section of said tire. Fig. 3 is a r similar to Fig. l., showinganother form of my invention. Fig'. i is a plan of the forni ot tireshown in Fig. 3.

is a view similar to i, showing still another form oit my invention.Fig. 6 is a View similar to showing the ribs on one oia the tirestaggered relative to those on the other side.

is thus illustrated, and referring to Figs.

and. invention comprises a rubber ase portion fr, a solidand continuoustread ortion B integral therewith, and. the lateral 'rejections or ribsC, said ribs occupying wie "eral channels formed between the up )ersin-faces o. ot the base and the side surfaces Z) olf the tread portion.As shown in `Figs.. .l and the surfaces b are vertical and parel beingfighe angles with tread surface 1 ot' the tire.

linvnino ti. lnofrz, a'

The outer side surfaces o of the ribs are straight and inclined inwardlytoward the tread of the tire, when the latter 1s viewed in crosssection, the upper ends of these sides o being connected by short curveso1 with the tread surface of the tire, and the lower ends of these ribsbeing connected by concave curves o2 with the-outer edges o1 of thetire. rlhese ribs C are, therefore, substantially triangular in shape,as shown in Fig. l, being tapered upwardly oroutwardlykthat is to say,in a direction away from the axis of the Wheel, and this taperingformation causing each rib to disappear or become practically nothing bythe time the plane of the tread surface `is reached. Thus the tapered orreduced ends of these ribs form no part of the `normal tread of thetire, notwithstanding the fact that the spaces between thcse ribs areopen at the tread-that is to say, these spaces are not covered at theirouter ends, and are exposed to the ground `when the tire is in action.As shown in Fig. l, these ribs C can be 'radial to the axis o" thewheel, and can be spaced apart in any suitable or desired manner; but asshown in Fig. 2 these ribs are arranged tangentially, being all.inclined in the same direction, whereby each rib 'isiexed or bentbackward toward the base of the tire when the tire is on the ground andin action. This adds to the resiliency of the tire, and at the same timethese ribs serve to prevent, or tend to prevent, lateral displacement ofthe tread portion of the tire, or side roli as it is sometimes called.Considerable compression of the tire, when on the ground, may bring theouter ends of the ribs C into contact with the surface of the street,and in such case a more or less non-skidding etl'eet is produced; butwhen not under compression the tread of the tire is formed only by theflat surface between the rounded corners b2 at each side thereof.

As shown in Fig. 3 the construction is the same as that shown in Figs. land 2, except that in this case the ribs D, which correspond to the ribsC, have straight sides d', or straight outer surfaces, extending'directly from the rounded edges b2 to the iorv'er edges el, wherebythese ribs D are more triangular in shape than those previously shownand described. In this case the tapered or reduced outer ends 'of theribs have lese opportunity or possibility of orniingpart oi the treadIlwhen the tire 1s i under heavy compression, than is' the case -the ribsD are dispose withthe ribs shown in Figs. 1 and 2: It will be understoodthat the ribs D canvbe either radial or tangential, as previouslydescribed and explained.

As shown in Fig. 4, the s aces d1 between opposite each other-@that isto say, those at one side of the tire are opposite those at the otherside thereof; but in` Fig. 6, -it will be seen, the ribs at one side ofthe tire are opposite the spaces at the other side, so that the ribs ofopposite sides have a staggered arrangement relative to each other.

' As shown in Fig. 5 the construction is like that shown in Figs. 1 and2, except that in this case the tread portion E tapers inward or towardthe axis of the wheel, when the tire is viewed in cross section,`wherebythe sides e are not vertical and parallel, but are oblique and` disposedat an angle to -each other, being closer together at the base of thetire than at the tread thereof. This formation will give addedresiliency, owing to the reduction of the rubber between the base andthe tread of the tire, whereby the ribs are caused .to sustain more ofthe weight.'

Thus in each case ,and in every 'form of the invention the triangularribs taper to,-

:ward the tread of the' tire, when the latter 1s viewed in crosssection, and .each rib be Vcomes practically nothing by the time itreaches the tread or tread portion which engages the ground. Owing totheslight curving or -rounding of certain portions, the

ribsv are not entirely a sharp cornered or v perfect triangle, but theyare substantially 6i fiat sided and triangular in form when the tire isviewed in cross section. The said ribs are, 1t will be seen, 1n thegeneral form of a right angle triangle, an acute angle tri` angle, anequilateral orsosceles triangle, when the tire is viewed in crosssection, or any other similar formation,

.As previously stated, my invention relates in a general way to thegeneral class of rubber tires which are formed with special reference toresiliency, prevention of side roll,

non-skidding and other qualities or characteristics; but while providingin a measure against skidding, my invention is more concerned with theproblem of manufacture and the questions of resiliency, stability anddurability, and other considerations as well; and one of the objects ofmy invention is to provide an improved construction and arrangement,whereby certain features heretofore employed in tires of this kind arenot necessary.

With further reference to the spaces between the ribs` which are, asstated, silbstan= tially trianguifar in any case, as illustrated in thedrawings, it will be seen that the construction and arrangement aresuchY that' the ground below. -In other words, 'and' whenthe tread ofthe tire is on the ground, the spaces at each side thereof overhang thetread and are set outwardly therefrom to such an extent that nothingintervcnesl'bef tween them and the ground. Thus the ribs are disposedimmediately at opposite sides of the tread, sothat the tread is directlybetween the two series' of ribs, and whereby the tread is supportedagainst lateral displacement throughoutthe entire body thereof. In otherwords, these ribs tend to yieldingly resist such lateral displacement ordistortion of the tread, for when the tread is under compression theribs at one side are crewded outward and away from the ribs at the otherside.

It will also be seen that when the ribs are arranged tangentially, andwhen the tire is under compression on a smooth ground surface, such as apaved road, the operation is as follows -The tread of the tire iscompressed until one of the sides of each rib which faces the next ribis in contact with the ground, and this contact along the tangentialside surface of the rib increases as the compression of the treadincreases, and thus the ribs become defiected from their tangentialpositions when. the tire is'viewed from the side thereof; but it will beunderstood, of course, that the ribs then straighten out and assumetheir normal tangential positions as soon as they leave the ground. Atthe same time, however, and while the tread is thus under compression,the outer sides of the ribs (the sides which face outwardly away fromthe tire) are also brought into contact with the grolmd, to some extent,and this is especially true when theztire lurches to one side.

for in such case the ribs lhave a tendency to roll under the tire andthereby increase the non-skidding effect thereof.

What I claim as my invention isz- 1. A rubber tire for vehicle wheelscomprising a base. portion and a tread portion. 'the base portion beingWider than the tread of the tire, and ribs exposed to the ground andextending from the base across the sides of the tread portion, spacedapart along the sides of the tire, the outer sides of said ribs beinglinclined relative to the sides of the tread portion in such a mannerthat each rib in effect tapers gradually away from the base, being threecornered and substantially triangular in shape when the tire is viewedin cross section, and said tapering causing each rib to becomepractically nothing by the time' it reaches the terminal then/vof at thetread of theytire.

2. A rubber tire for vehicle wheels comprising a base portion and atread aortion.

/tlfe base portion being wider than t, tread .ribs

ineaeae i and extending from the base across the sides of the treadportion, spaced apart along` the sides of thetire, the outer sides ofsaid being inclined relative to the sides of the tread portion in sucha. manner that each rib in -eilect tapers gradually away from the base,when the tire is viewed in cross section, the spaces between the ribsbeing accessihle vertically from the ground at each side el" said tread,and said taperingcausing each rib to become practically nothing by thetime it Ireaches the terminal thereof at the tread loi" the tire, saidribs being disposed in position to engage the ground when the tire iscompressed and arranged tangentially oi the wheel.

l 8. A rubber tire iior vehicle Wheels coniprising a base portion and asolid tread portieri, the base portion being wider than the tread ot'the tire, and ribs exposed to the ground and extending from the baseacross the sides of thc' tread portion, spaced apart along the sides ofthe tire, the outer sides oi' said ribs being inclined relative to thesides oi the tread portion in such a .manner that each rib in effecttapers gradually away from the base, each rib thereby presenting a.triangular outline when the tire is viewed in cross section, and saidtapering causing each rib to become practically nothing by the time itreaches th'e terminal thereof at the tread of the tire, said treadportion being continuous` whereby the peripheral tread surface of thetire is formed only .by the unbroken area ot uniform width between theouter corners of the solid tread portion.

4. A rubber tire for vehicle Wheels comprising a base portion and atread portion, the base portion being wider than the tread of the tire,and ribs extending from the base across the sides of' the tread portion,spaced apart along the sides of the tire, said ribs being arranged tocontact with a flat ground surface only when the tread is undercompression thereon, the outer sides of said ribs being inclinedrelative to the flatsides of the tread portion in such a manner thateach rib in eflect tapersgradually away from the base and each rib,being substantially triangular when the tire is Viewed in cross section.

5. A rubber tire for vehicle Wheels comprising a base portion and atread portion, the base portion being wider than the tread of the tire,and ribsextending from the base across the sides of the tread portion,spaced apart along the sides of the tire, the outer sides of said ribsbeing inclined in such a manner that each rib in eilect'tapers graduallyaway from the base, being substantially triangular when tire is viewedin cross section, and said tapering causing each rib to becomepractically-nothing by the time it reaches the terminal thereof at thetread of the tire, said ribs engaging the ground to an extent dependingupon the degree of coniipresrlon of said tread.

(l. A rubber tire tor Vehicle wheels, comL prising a base portieri and atread portion, said tread portion in cross section tapering with flatsides toward said base, and ribs extending vtroni the base across thesides ot the tread portion, spaced apart along the sides of the tire',said ribs being arranged to engage a flat ground surface only when thetread is under compression thereon, and each rib in eiiect tapering away'from the base and being substantiallyy triangular in forni 'when thetire is viewed in cross section.

7. A rubber tire for vehicle wheels, coinprising a base iportion and atread portion, and ribs' extending troni the base across the sides olithe tread portion, spaced apart along the sides of the tire, each rib inei'liect tapering away from the base and being substantially triangularin is viewed in cross section, said Atapering causing each rib to becomepractically nothing by the time it tern'iinates at the tread of thetire, and said r'bs engaging the ground in thc pla-ne of said tread toan extent depending upon the degree oit compression of said` tread.

8. A rubber tire for vehicle wheels, comprising a. base portion and atread portion, and ribs extending' from the base across the sides of thetread portion, spaced apart along the sides of the tire, each rib ineffect tapering away from the base and being substantially triangular inforni when the tire is viewed in cross section, said ribs therebyforming substantial lateral supports to brace the tread portion againstside roll and yieldingly resist compression thereof, the arrangement ofthe ribs being suoli that they are tangential and subject to contactwith the ground when the tire is on the wheel.

9. A rubber tire for vehicle wheels, cornprising a base portion and atread portion, and ribs extending from thev base across the sides of thetread portion, spaced apart along the sides of the tire, each rib inel'ect tapering away from the base and being substantially triangular inforni when the tire is viewed in cross section, said tapering causingeach rib to become practically nothing by the time it terminates at thetread of the tire, and said ribs engaging the ground in the plane ofsaid tread to an eX- tent depending upon the degree of cornpression ofsaid tread, the arrangement of the ribs being such that they aretangential when the tire is on the wheel.

l0. A rubber tire for vehicle wheels, coniprising a tread portieri whichtapers toward the wheel in cross section, and ribs which taper awaytrein the wheel when the tire is viewed in cross section, disposed alongthe forni when the tire `opposite sides of the tire, said ribs engagingthe'ground to an extent depending upon the degree of compression of saidtread.

11. Arubber tire for vehicle wheels, comprising a tread portion whichtapers toward the Wheel in `cross section, and ribs which taper awayfrom the Wheel 'When the tire is viewed in cross section, disposed,along the opposite sides of the tire, said ribs engaging the ground toan extent depending upon the degree of compression of said tread, andsaid ribs When not distorted being tangential relative to the Wheel.

l2. A rubber tire for vehicle Wheels, comprising a tread portion whichtapers to Ward the Wheel in cross section, and ribs thisB day of April1914 ALVARO S. KROTZ. Witnesses:

F. H. FARNSWORTH, D. DONNELLY.

